1.The second half of The Lovely Bones having so much emphasis on Susie's dad looking for her killer, making it seem more like a murder mystery.

Paramount Pictures

"The book is a rumination on the loss of a loved one, and the story of how Susie’s death destroys and eventually brings back together her family. Not only did it ruin the poignancy of the entire movie, but focusing on the search for her killer also dramatically reduced the family’s part in the story when they are just as important as Susie is in the book."

2.Changing the ending of Inkheart in such a way that there wouldn't be scope for sequels based on the subsequent books in the trilogy.

3.Setting The Girl on the Train in New York.

Universal Pictures

"A major element of the book was the London commute where the plot physically makes sense – there's no way there would be a train line in the back garden of a house like that in New York but you see it all the time in London! It's also a major element of the book tonally and atmospherically. I mean, they kept Emily Blunt British so I just don't understand why the setting had to change!"

4.Making the end of The Dark Tower much less dark.

Columbia Pictures

"The ending was probably the worst of it – in the book, Roland lets Jake fall to his death. THAT’S THE WHOLE POINT. The character is so focused on revenge and his 'quest' that he allows a child to be killed rather than give up on it. It’s a powerful and agonising scene, one that informs the rest of the series. In the movie? The kid lives and Roland invites him to come along on adventures like it’s some Disney cartoon. They teased this film for 10 years, I was so excited for it, and what I got was a slap in the face."

5.Having Voldermort disintegrate at the end of Harry Potter and the Deathly Hallows: Part 2.

Warner Brothers

"I could fill books with the problems I have with the Harry Potter adaptations. But the death of Voldemort pissed me off the most. In the books, it was so important that he just fell down when he was killed. Dead and cold and still, like any other human because in the end that's all he was. The whole dramatically crumbling and exploding into ashes thing was dumb and kind of ruined the entire point in my opinion."

6.Alice having a vision at the end of Twilight: Breaking Dawn, when she's not meant to be able to have visions that include the werewolves.

7.Making the characters older in the Percy Jackson movies.

20th Century Fox

"If you wanna talk about inaccuracies, all of the Percy Jackson movies. But if I had to pick one it would be the fact that they weren’t 12. It shouldn’t have been so hard to find some talented 12-year-old looking kids. Like the director Chris Columbus said that he didn’t think the plot was believable with 12 year olds and yet he directed the first two Harry Potter movies where (guess what!) THEY WERE 11 AND 12!!!!!"

8.Pretty much everything about Miss Peregrine’s Home for Peculiar Children.

20th Century Fox

"The children’s ages and powers were changed in order to force an unnecessary romantic subplot between Olive and Enoch, completely erasing the relationship between Fiona and Hugh. They also made Fiona talk, completely erasing her backstory and characterisation. They made Emma weak and submissive rather than the badass powerhouse she was in the books. Bronwyn was turned into a cute little girl for the sake of laughs, thereby taking away her motherly demeanour towards the younger children.

"And the whole plot with the hollowgasts and wights being changed has made it impossible to make any more of the books into movies. There is so much more wrong with it that I haven’t even mentioned. If I tried to list them all i’d be typing all day."

9.Making the plot of Ella Enchanted about an uncle who doesn't exist in the books.

Miramax Films

"They left out the entire plot at finishing school where she befriends fellow outcast Areida, who’s picked on for her foreign accent and lower-class status. Instead they created the cliche 'uncle wants to kill the prince and steal the crown' narrative, and the uncle doesn’t even exist in the books. JUST MAKE THE MOVIE ABOUT ELLA INSTEAD OF 'GUY' STUFF, YOU HAD ANNE HATHAWAY AND BLEW IT."

10.Cramming two books into one in Queen of the Damned.

Warner Bros. Pictures

"The studio completely botched this one, first by trying to cram two books (The Vampire Lestat and Queen of the Damned) into one, then making it even worse by muddling the entire story, along with not-so-great casting."

11.Completely changing the ending of My Sister's Keeper.

New Line Cinema

"I was disgustingly angry. GRANTED, I was angry enough that I threw my book across the room 50 times before I was finished reading it but when they change the ending of the movie, they completely took away from what the author was trying to get across when she wrote it."

12.Giving the dad amnesia in the movie of A Little Princess, even though in the books he dies and she gets adopted.

Warner Bros. Pictures

"In the movie, the dad lives because of amnesia. In the book he dies and the kindly man next door adopts her. Frustrated me as a kid. Disney kills off parents left right and centre and they think we can't handle a dad passing away at war?"

14.Sookie not marrying Sam on True Blood.

15.Altering the ending of The Golden Compass and messing up the order of the books so that it's not set up for the next story.

Warner Bros. Pictures

"That was one of my favourite books when I was younger, and I was super excited with the casting. Then they decided to completely change the order of the books so that the movie made no sense and took away the super dramatic ending that sets off the next two stories. It was terrible!"

16.Peeta never losing his leg in The Hunger Games.

Lionsgate

"It plays a huge part in the second book and makes why they are split up in the end of the book a lot more believable than Peeta just being okay being separated from Katniss in an arena where people are killing each other."

17.Harry Potter's parents always looking in their forties in the films despite being in their early twenties when they died.

18.Merging two characters from the Water for Elephants book into one person in the movie.

20th Century Fox

"August (head animal trainer) and Uncle Al (owner of the circus) are merged into one person and you lose the a lot of the story development because the abusive husband is merged with the ruthless circus owner to create an all-round evil character."

–Jennifer Pate via Facebook

19.Dragging out Ezra and Aria's relationship on Pretty Little Liars.

ABC

"In the books, Ezra and Aria's relationship was found out quite fast and he was fired and left town in disgrace, which is what SHOULD happen when a high school teacher starts a relationship with his underage student."

–Beverley Carry via Facebook

Submissions have been edited for length and/or clarity.

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